得到的图theta2和答案不一样，不知道为什么，需要再检查！！！！！

"""niku 习题5.8"""""" 乘除法要用数组  将列表转换为数组"""import numpy as npimport matplotlib.pyplot as pltimport math  plt.figure(figsize=(8,4))""" 求theta1""" t =  np.arange(1,12,1)#生成一个数组，不是列表px = list(np.array([3]*11))py = list(np.arange(5,-6,-1))pz = list(np.array([5]*11))theta1=[0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.]theta2=[0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.]theta3=[0.,0.,0.,0.,0.,0.,0.,0.,0.,0.,0.]for s in range(0,11):    a =math.atan2(px[s],py[s])    theta1[s] = a#print(theta1)   """求theta3""" for s in range(0,11):    f = math.acos(((py[s]/math.cos(theta1[s]))**2+(pz[s]-8)**2-162)/162 )        theta3[s] = f#print(theta3)    """求theta2"""for s in range(0,11):    q = math.cos(theta1[s])*(pz[s]-8)*(1+math.cos(theta3[s]))+py[s]*math.sin(theta3[s])    e = 18*(1+math.cos(theta3[s]))*math.cos(theta1[s])    t = math.acos(q/e)    theta2[s] = t*180/3.1415    for s in range(0,11):    t = theta1[s]    theta1[s] = t*180/3.1415for s in range(0,11):    t = theta3[s]    theta3[s] = t*180/3.1415"""开始画图 画图的时候要用数组"""t = np.arange(1,12,1)theta1 = np.array(theta1)theta2 = np.array(theta2)theta3 = np.array(theta3)plt.plot(t,theta1,label="$theta1$",color="red",linewidth=2)plt.plot(t,theta2,label="$theta2$",color="blue",linewidth=2)plt.plot(t,theta3,label="$theta3$",color="green",linewidth=2)plt.ylim(-20,180)plt.xlim(-1,12)plt.xlabel("point")plt.ylabel("theta")plt.legend(loc="upper left")plt.grid(True)plt.show()